Archive for August, 2011
Life Cycle of an Angiosperm
Angiosperms are plants that produce flowers, which are nothing but the reproductive machinery of the plant. The life cycle of angiosperms begin with pollination and end in the formation of fruits which contains seeds that germinate into new plants which mature till they reach the flowering stage, thereby, completing a full circle. Now, before we discuss the details of the life cycle of angiosperms, let’s check out the different parts of the flower that participate in the reproductive cycle to continue the species even after the parent plant dies or withers away.
Parts of Flower that Participate in the Reproduction Cycle
Following are those parts of a flower that actually facilitate the entire reproductive mechanism which results in the production of seeds. This seed, when it finds a combination of favorable environmental conditions (right kind of soil, adequate moisture, sufficient amount of air and temperature, etc.), sprouts into seedlings, which then grow into plants. On reaching maturity, the new, young plants grow flowers themselves, and the process starts all over again.
Stamen: This is the male reproductive part of a flower, and it consists of a long, slender filament, which can be seen occurring as a number of long, pliant stalks arranged in a circle on the inside of the flower, surrounded by petals. These filaments are topped with small, often oblong, head like structures known as anthers. The stamen is where the pollen grains are produced, and these pollen grains are carried from the anthers to the female reproductive organ, where they fertilize the ovules, but we’ll discuss that later. So, to put it simply, male parts of a flower = stamens = filaments + anthers!
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The Common Types of Chemical Reactions
In our daily life, we encounter a number of chemical reactions, although we may not always think of the chemistry hidden within those principles. The mere melting of an ice cube kept in a glass, boiling of water, burning of wood, smoke ejecting from vehicles – all are classic examples of common chemical reactions in our daily lives. In middle and high school chemistry, students are introduced to a large number of reactions. Students must understand that most of the chemical reactions follow a certain order. So instead of just memorizing individual reactions, it is better to understand the way each group of reactions proceed to form desired products. That will make it easier for students to predict the products of a reaction in several other cases of chemical reactions.
Examples of Common Chemical Reactions in Chemistry
Every natural process is an example of a chemical reaction. A battery converts chemical energy into electrical energy, by following some specific reaction. Similarly, burning of a log of a wood, in the presence of oxygen is another reaction leading to products like carbon dioxide and heat energy. Some more common chemical reactions examples have been discussed further.
Synthesis or Combination Reaction
This is the simplest reaction that occurs in nature. When two or more chemical elements or compounds react to form some specific product(s), it is called synthesis. It is in of the form: A + B → AB
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What is Fermentation?
Do you know what is common between curd, wine and beer? They are all formed by the process of fermentation. But what is fermentation? A simple fermentation definition can be: the process of breaking down of complex substances into a simpler form. The history of fermentation is very old. The process of fermentation was used in making beverages such as beer and wine, since as early as the year 7000 BC. Later on, the process was used to make many milk products like curd and cheese. The science of fermentation is known as zymology, and Louis Pasture was the first zymologist who is known for his research on yeast and the fermentation process. So let’s find some more information on the fermentation process in the following paragraphs.
What is Fermentation in Biology?
In biology, the fermentation process is actually a conversion of sugar into acids or alcohol with the help of bacteria or yeast. The bacteria help in the conversion of sugar into acid, and the yeast is used for the alcohol production. Many people wonder, is fermentation aerobic or anaerobic? The answer to this is that fermentation takes place in anaerobic conditions or in the absence of oxygen. The process of fermentation initially resembles the process of glycolysis. In the first step of glycolysis, glucose is broken down into pyruvic acid, ATP and NADH. After this process the NADH is further re-oxidized and CO2 and the end product which can be either alcohol or acid, depending upon the organism performing the fermentation process, is released. So, we can say that fermentation is a chemical process.
Fermentation Examples
Following are some examples of fermentation, which will help you to understand the process and uses of it.
Beer is one of the best examples of anaerobic fermentation. It is made out of grains like wheat, barley, etc. The grain is dried and then mashed properly. This is then mixed with hot water. Then this mixture is kept in a fermentation vessel and then yeast is added. The vessel is then left for a few weeks in anaerobic conditions. In this condition, the yeast eats the sugar or carbohydrates and forms alcohol. After a considerable period of time, the beer is taken out from the vessels, filtered and then packed in the bottles. Read the rest of this entry »